The use of boron clusters in the rational design of boronated nucleosides for neutron capture therapy of cancer

Boron neutron capture therapy (BNCT) is a chemoradio-therapeutic method for the treatment of cancer. It depends on the selective targeting of tumor cells by boron-containing compounds. One category of BNCT agents that has received extensive attention during recent years is boronated nucleosides. Such structures may be converted to the corresponding 5'-monophosphates by phosphorylating enzymes and thereby entrapped in tumor cells by the virtue of the acquired negative charge. This review analyzes previous design strategies applied in the synthesis of boron cluster-containing nucleosides and discusses possible future developments in this field based on existing knowledge of enzyme tissue expressions, enzyme substrate specificities, and contemporary trends in rational drug design. (C) 2000 Elsevier Science B.V. All rights reserved.